Introduction
Apache SpamAssassin examines incoming emails and tests for spam characteristics by evaluating specific parts of an email. It uses Bayesian filtering techniques as well as network tests to screen for incoming email. This results in an overall score that Apache SpamAssassin uses to determine whether it should discard a message.
In this guide, we cover how to customize SpamAssassin from the cPanel interface by going to Home >> Email>> Spam filters and explain which tools are available to cPanel users.
Bayesian filters
Bayesian analysis is used by SpamAssassin to evaluate incoming and outgoing email headers and its content to determine the probability that it constitutes spam.
The cPanel >> Email>> Spam Filters interface provides users with the following options:
- Process new emails and mark them as spam; This option must allow usage of the proceeding options.
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Spam Box; Move New Spam to a Separate Folder.
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Auto-Delete; Automatically Delete New Spam.
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Advanced Additional Configurations.
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Whitelist; Always allow.
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Blacklist; Always deny.
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Calculated Spam Score Settings; Customizations to the weighted SpamAssassin score options.
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Let us look at the options we mentioned above; Starting with Spam Box, when this is enabled, it would send emails marked as spam to a Spam box created after enabling the option. See the attached screenshots:
After enabling the Spam Box option, you can manage it from the "Configure Spam Box Settings" link, which provides you with options to delete spam messages:
Auto-Delete: This option would activate the automatic deletion of emails classified as spam when they exceed the Spam score threshold:
Advanced Configurations
Let us examine the "Advanced Additional Configurations" which allows the fine-tuning behavior of SpamAssassin. The first option we want to look at is "Whitelist":
This option allows the cPanel user to white-list incoming emails from specific accounts, which means SpamAssassin would not prevent email delivery to the user's inbox.
Whitelist
To whitelist a domain simply click on "Edit Spam Whitelist Settings" and add the desired domain, for example:
Notes:
- The wildcard (*) symbol whitelists all email IDs from @cpanel.net for example info@cpanel.net or status@cpanel.net and so on.
- If you whitelist multiple email addresses, each email address will need to have its own entry by using the "+ Add A New "whitelist_from" Item". There is not a delimiter to enable bulk additions.
Blacklist
This option allows the cPanel user to block email accounts from reaching the email accounts regardless of the spam score, example:
Notes:
- The wildcard (*) symbol whitelists all email IDs from @cpanel.net for example info@cpanel.net or status@cpanel.net and so on.
- If you blacklist multiple email addresses, each email address will need to have its own entry by using the "+ Add A New "blacklist_from" Item". There is not a delimiter to enable bulk additions.
The final option we will review is "Calculated Spam Score Settings" which provides fine-tunning of which specific object would SpamAssassin consider as a high probability of spam. For example:
Scores represent the specific object SpamAssassin uses to test incoming emails, for example:
The above would add a high Spam score to incoming emails with the following criteria:
Mentions millions of (dollar) ((dollar) NN,NNN,NNN.NN)
Detail information about each of the scores in the dropdown can be found here:
https://spamassassin.apache.org/old/tests_3_3_x.html